The present invention generally relates to an image sensor and more particularly, to a method of manufacturing a contact type one-dimensional image sensor which is provided with a photoconductive material composed of a Group II-VI compound semiconductor containing Cd, or more than two kinds of such compound semiconductor as a photoelectric converting film, employing a real time reading system and a matrix wiring drive, and also relates to a contact type image sensor module substrate produced by such method.
For manufacturing a photoelectric converting film of a long length or of a large area, there have conventionally been employed various thin film preparing techniques such as a vacuum deposition method, sputtering method or glow discharge chemical vapor deposition method, etc.
Furthermore, in order to improve resistance against environmental conditions of the element using the photoelectric converting film prepared through employment of the thin film manufacturing techniques as described above, protection of the photoelectric converting film has been effected by various organic resin films or inorganic insulating films.
In the conventional thin film manufacturing techniques as described so far, film characteristics depend on manufacturing techniques of production apparatuses to a large extent, and there are still problems to be solved in the aspects of yield and reliability. For example, in the case where amorphous silicon thin films are to be produced by the reactive sputtering method or glow discharge vapor growth method, etc., techniques of a high degree are required for the control of glow discharge and plasma, and thus, it becomes rather difficult to achieve uniformity in the reproducibility and film characteristics.
Meanwhile, for producing a thin film of a Group II-VI compound semiconductor containing Cd by the sputtering method or vacuum deposition method, etc., deviation from stoichiometric composition delicately varies according to the manufacturing conditions, and there has been such a serious disadvantage that a sufficient reproducibility can not be achieved, depending on the manufacturing conditions, in the activating treatment by doping of halogen compounds such as of Cd, Cu, and Ag, etc. for imparting photoconductivity.
Moreover, in the conventional element manufacturing methods, cost tends to be increased since an extra process is required for the formation of the protective film for the element.